With any software, the more you use it, the more hacks and shortcuts you discover, and never a truer word has been said when ...
The first reason why you might see double square brackets in a structured reference is that the column headers they refer to contain a special character. In these cases, the extra pair of square ...
Normally you will use Stacked Image Column to show a relationship of images. The name of the relationship comes first, followed by a period, followed by the name of the column to display: ...